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Google's official python tutorial violates PEP8, recommends python 2.4-2.6, and my university just assigned it to us.
https://developers.google.com/edu/python/set-up

/r/Python
https://redd.it/7nr322
Serial Programming [Help]

I tried to send data to a fingerprint sensor but the the write() method just returns different integers if I use different argument hex values.


>>> import serial
>>> ser = serial.Serial('/dev/ttyAMA0', baudrate=9600, timeout=0.5)
>>> ser.write('\x01')
1

The fingerprint doesn't seem to initialize. I tried checking it by cranking up the LED to see if the sensor is initialized, but the LED doesn't seem to work either.

/r/Python
https://redd.it/7ns474
Tkinter or pygame?

Hi everyone,

Currently creating my beginners game design class for 14-15 year old students. The school's IT team is struggling to install pygame and is contemplating giving me a set of *nix laptops as it is much easier to install pygame. However as I will be new at this school I don't want to get the IT team annoyed at me, I am thinking that maybe I should use tkinter instead. I only need to give my students a taste of python as we will be using game maker for the majority of the time ( as the next unit we will be exploring python in depth and will be using cloud 9 edu so I have full control over the environment they are using). My husband who is a professional python programmer hates tkinter (cites a bad experience when he was learning python as his reason) and feels that I should persist and ask for pygame. I haven't had an issue with tkinter but now I am second guessing my choice. Is using tkinter a suitable choice for creating a simple game?

/r/Python
https://redd.it/7nta74
Make python run like an app on terminal

Ok so Im having a really hard time describing what im trying to do but here goes.


So I want to make a countdown thingy. But I want it to do the following things:

1. Empty the screen (including the line that shows the user and the current directory on the terminal)
2. I want to output the the current number in the countdown and only the current number (i want to "erase" the previous number and have the current one appear on the same line)

Im having trouble doing these things because I don't know how to describe what I want to do in a way that I can google it. I don't need anyone to post the code to do those things here, I just need someone to kind of tell me what im trying to do in python terms I guess.

/r/Python
https://redd.it/7nt6vh
Django 2.0 giving Foriegn key constraint error when saving a custom user?

I'm learning how to make a custom user in django, so i followed the guide here : https://docs.djangoproject.com/en/2.0/topics/auth/customizing/

Near the end of the guide it shows a complete sample code on how to make a custom user. I made my own user using the guide and it works fine when i'm creating a superuser in terminal but it throws error when I try to add a new user through the admin.

The error says Integrity Error FOREIGN KEY constraint failed. I really don't understand it. At first I though I had made some mistake in the code so I made another test project and basically copy pasted the code available on the guide and it still throws this error.

Can someone guide me as to what is the reason? I tried looking for the source of error and have had no luck. Would really appreciate your help.

Thanks!

/r/djangolearning
https://redd.it/7ntilf
What is the ForeignObject field type?

So i'm working on some models for a new django project (I'm pretty new to django myself) and I'm wondering what the difference between using

some_field = models.ForeignObject(MyClass)

and this

some_field = models.ForeignKey(MyClass, on_delete=models.CASCADE)

**What are the pros and cons of one over the other?** I control+f'd for ForeignObject in the model documentation for django on their site and I can't seem to find any answers to the above question, and some google searching doesnt turn up any results for the specific term either.

Thoughts?

/r/django
https://redd.it/7nsnzn
Help with the Django Cache Framework

Hey everyone,

I'm wondering if someone could help me get to know the django cache framework for a (hopefully) simple task. I'm developing a [financial analysis application](https://join.lazyfa.com) and I would like to cache some portions of the first load of the page to be reused in other sections of the app. Here's the example I'm trying to figure out right now:

When a user sends a ticker through (e.g. AAPL) this is [the dashboard that pops up](https://imgur.com/GOWqPig). Some parts of that dashboard are done in the dashboard view. Others (for example company SIC, short %, float, profile, etc) are pulled from external sources via ajax calls and a few others (e.g. calculations like burn rate, averages, etc) are populated dynamically by making ajax calls to other views.

That part all works fine. The dashboard loads in a couple seconds and whatever doesn't load gets pulled in via AJAX as the user uses what's available.

Now when a user switches to the red flags > income statement section, I'd like to keep the entire company summary section (Overview, Company Information, Recent News) in cache so it doesn't have to be retrieved again. So in the dashboard view, after doing all the biz logic to return the context used in the ajax calls, I just set a cache key ('context') to the context and store it for some amount of time. For example, just storing it for 60 seconds:

# Do stuff to set all these dicts and stuff that's used on the dashboard, then...

template = 'dashboard.html'
context = {
'ticker': ticker,
'companyInfo' : companyInfo,
'database' : database,
'annual_dict_most_recent' : annual_dict_most_recent,
'quarterly_dict_most_recent' : quarterly_dict_most_recent,
'ttm_dict_most_recent' : ttm_dict_most_recent,
'annual_dict_most_recent' : annual_dict_most_recent,
'quarterly_dict_most_recent' : quarterly_dict_most_recent,
'ttm_dict_most_recent' : ttm_dict_most_recent,
'INCOME_COLLECTION' : INCOME_COLLECTION,
'BALANCE_COLLECTION' : BALANCE_COLLECTION,
'CASHFLOW_COLLECTION' : CASHFLOW_COLLECTION,
'METRICS_COLLECTION' : METRICS_COLLECTION,
'INCOME_Q_COLLECTION' : INCOME_Q_COLLECTION,
'BALANCE_Q_COLLECTION' : BALANCE_Q_COLLECTION,
'CASHFLOW_Q_COLLECTION' : CASHFLOW_Q_COLLECTION,
'METRICS_Q_COLLECTION' : METRICS_Q_COLLECTION,
'jsonTickerList' : jsonTickerList,
}
cache.set('context', context, 60)

return render(request, template, context)

Then when a user clicks the income statement link, I can do this in the relevant view:

context = cache.get('context')
template = 'income.html'
return render(request, template, context)

That works perfectly and loads the whole company summary section from cache, but there's a slight problem: If a user searches for a ticker, then opens a new tab and searches for a new ticker (e.g. TSLA), the cache is overwritten because of the new dashboard load, so if they go back to their previous tab with the dashboard for AAPL on it, when they click the income statement link it will load the company summary for TSLA.

I understand why this is happening but I'm just not sure how to handle it cause I don't fully understand the capabilities of the caching framework or what the best way to handle this would be.

Could someone more familiar shed a bit of light on this for me? Thanks so much!








/r/django
https://redd.it/7nrt3y
[D] Results from Best of Machine Learning 2017 Survey

Results from

https://www.reddit.com/r/MachineLearning/comments/7mjxl4/d_vote_for_best_of_machine_learning_for_2017/

If you missed that thread and there's something you want to mention, post it and I'll put it up. Lots of categories didn't have an entry. You can also make a category yourself.

######**Best Video:**

aurelien geron's capsule networks explanation.

https://youtu.be/pPN8d0E3900

######**Best Blog post:**

Luke Okden-Rayner's criticism of ChestXray14 dataset.

https://lukeoakdenrayner.wordpress.com/2017/12/18/the-chestxray14-dataset-problems/amp/#click=https://t.co/52PSslbAh8

######**Best New Tool:**

Pytorch

"and we all realized what a pain in the ass Tensorflow was and how it didn't need to be that way. In the academic community, it certainly to me feels like pytorch has become the dominant framework (probably not backed up by actual stats... But my school's CV research lab has certainly switched over)"

######**Best Blog Overall:**

Ferenc Huszar's inference.vc

>
> I might have nominated distill.pub instead, but they (and I) consider themselves a journal, which puts them out of the running.
>
> Writing good blog posts is hard, and as such, I feel like it's fair to weight consistent posting. Signal to noise is the primary problem with following blogs (I'd much rather follow a blog that posts one great article a year than a blog that posts 12 articles a year of which 2 are great).
>
> Thus, I've found all of the articles I've read from Ferenc to be insightful.
>
> One other thing: I don't really expect "novel" insights out of blog posts. I think blog posts are best served as a distillation of the current state of research, and sometimes an explanation of ideas. If they have new insights, they'd prolly be writing a paper :)
>
> Some highlights (apologies if there are any highlights from the posts I haven't read):
>
> http://www.inference.vc/my-notes-on-the-numerics-of-gans/
>
> An insightful post into one of the problems GANs face in optimization, framed in the form of vector fields.
>
> http://www.inference.vc/design-patterns/
>
> Really unified and explained to me how all these different machine learning tasks are just optimizing over a loss surface and approximating gradients.
>
> There's a couple other blogs I think deserve honorable mentions, including Sebastian ruder's. I think I might write a meta blog post talking about these other blogs one day.

Runner up:

Berkeley AI Research blog.

http://bair.berkeley.edu/blog/


######**Best Papers:**

Tied

Deep Image Prior

https://dmitryulyanov.github.io/deep_image_prior

Quantile Regression for Distributional RL

https://arxiv.org/abs/1710.10044

######**Best Reddit Post:**

https://www.reddit.com/r/MachineLearning/comments/6l2esd/d_why_cant_you_guys_comment_your_fucking_code/


######**Best Reddit Project:**

https://www.reddit.com/r/MachineLearning/comments/72l4oi/pfinally_managed_to_paint_on_anime_sketch_with/?st=jbqezuqt&sh=a8aa336f

######**Best Course:**

New Andrew Ng deep learning coursera course

######**Best Youtube channel:**

3 way tie

3blue1brown

DanDoesData

2 minute papers

/r/MachineLearning
https://redd.it/7nrzhn
Temporarily work on media file.

Hi everyone. At the moment I'm doing a web app which is a collection of simple tools. One of them is a meme generator. I have the whole Python script already done, it runs well and now I have to put it into Django project. It works like that: user provides image and captions and it saves the meme to a directory.
And while I have and idea how could I incorporate it, I bet it can be done better and simpler. The obvious way to go about is to create a model that requires a file upload. Then the model created upon file upload would be passed into another view in url. Based on the image, the script would create a new, processed image and display it in the template.

But is there a better solution? I think the problem with this would be that over time and after some usage my VPS would be cluttered with images. So I would have to wipe the whole meme generator image directory but how? To not interrupt the user while creating the image. Plus, I think that making the script write to the directory could be troublesome. Is there a way to do it without model creation?

/r/djangolearning
https://redd.it/7nu2l6
Please share with me your method(s) of determining a specific location's timezone.

Hi folks; hope all is well.

If, for whatever reason, you must determine the timezone in which a location resides, how do you go about acquiring the information? You have the location's address.

The solution seems trivial on the surface -- query some existing location service; query an existing geo database; etc... -- but, as often the case, things aren't always trivial; or they are that trivial and there exists many solutions. So, as I'm doing my research, I'd like to have your input/enlightenment.

I appreciate your time.

/r/django
https://redd.it/7nvnak
[AF] How to use a docker image of flask on an instance

I am trying to use [this](https://github.com/tiangolo/uwsgi-nginx-flask-docker/tree/master/python3.6) docker image of flask with nginx and uwsgi on an amazon ec2 instance. I am following the readme in the same github repository.

I am really new to this, so I have no idea how this is supposed to look or what obvious stuff I am supposed to do beforehand. I copied all the files in the github above to my instance, so my directory looks like [this](https://i.imgur.com/fDnkiOH.png). I ran `docker build -t myimage .` and `docker run -d --name mycontainer -p 80:80 myimage. `docker ps -s`looks like [this](https://i.imgur.com/6cpDjrM.png). Yet when I go to my website [here](http://ec2-18-217-22-81.us-east-2.compute.amazonaws.com/), nothing shows up. I have done nothing else. What am I missing/doing wrong?



/r/flask
https://redd.it/7nsnwn
pomegranate v0.9.0 released: probabilistic modeling for Python

Howdy all!

I just released a new version of pomegranate. The focus of this version is on missing value support for all models in both the model fitting, structure learning, and inference steps for all models (probability distributions, k-means, mixture models, hidden Markov models, Bayesian networks, naive Bayes/Bayes classifiers). The general manner that this is done is by only collecting sufficient statistics from observed values, and ignoring missing values. This can frequently achieve better results than using common, simple, imputation methods.

* I've added documentation to the [readthedocs page](https://pomegranate.readthedocs.io/en/latest/) under the "Missing Values" section
* I've added an [extensive tutorial](https://github.com/jmschrei/pomegranate/blob/master/tutorials/Tutorial_9_Missing_Values.ipynb) on how missing value support is handled here
* I recently [gave a talk at ODSC west](https://www.youtube.com/watch?v=oF8BKWe9_i8) about pomegranate and the features recently incorporated (sadly before missing values were added).

The modular nature of pomegranate means that one can now use missing value support in conjunction with any of the other features. For example, one can easily add multi-threading to speed up models, or do out-of-core learning with incomplete data sets, or have both missing data and missing labels to do semi-supervised learning with missing data as well!

You can install pomegranate either by cloning the [GitHub repo](https://github.com/jmschrei/pomegranate), or with `pip install pomegranate`. Wheels should be built for all platforms soon, but some issues have delayed that. I hope to have them up soon, so you don't even need to deal with Cython.

As always, I'd love any feedback or questions!

/r/Python
https://redd.it/7nw5t0